Housing for centrifugal pumps

ABSTRACT

A centrifugal pump housing wherein the shaft sleeve, the cylindrical portion for reception of a stuffing box and a radial flange form a one-piece annular inlet section which is bolted to a wearing ring and a volute casing. The flange has several concentric annular ribs one of which is sealingly engaged by a single concentric rib of the wearing ring, or vice versa. This renders it possible to employ the same wearing ring for assembly with any one of several differently dimensioned inlet section, or to employ a single inlet section for assembly with any one of several differently dimensioned wearing rings.

United States Patent 11 1 Hanagarth et al.

HOUSING FOR CENTRIFUGAL PUMPS Inventors: Wolfgang Hanagarth; Richard Schaier, both of 6710 Frankenthal/Pfalz, Germany Klein, Schanzlin & Becker Aktiengesellschaft, 6710 Frankenthal/Pfalz, Germany Filed: Sept, 16, 1971 Appl. No.: 188,706

Assignee:

Foreign Application Priority Data Sept. 16, 1970 Germany P 20 45 685.3

U.S. Cl. 415/110, 415/219 Int. Cl. F0111 11/00 Field of Search 415/110, 219

[451 June 12,1973

3,512,788 5/1970 Kilbane 415/110 Primary Examiner-C. J. Husar Attorney-Michael S. Striker A centrifugal pump housing wherein the shaft sleeve, the cylindrical portion for reception of a stuffing box and a radial flange form a one-piece annular inlet section which is bolted to a wearing ring and a volute casing. The flange has several concentric annular ribs one of which is sealingly engaged by a single concentric rib of the wearing ring, or vice versa. This renders it possible to employ the same wearing ring for assembly with any one of several differently dimensioned inlet section, or to employ a single inlet section for assembly with any one of several differently dimensioned wearing rings.

ABSTRACT 9 Claims, 3 Drawing Figures HOUSING FOR CENTRIFUGAL PUMPS BACKGROUND OF THE INVENTION A are mounted in the interior of the housing are insertable and withdrawable at the suction side of the pump. In other words, the maximum number of suction lids has to equal the number of different pump sizes. That portion of the housing which is adjacent to the outlet side is fixedly connected with the volute casing, and such portion is normally provided with a flange of predetermined size for connection to the floor frame or base. Thus, a single base is capable of supporting any one of an entire series of differently dimensioned pump housings. In other words, a relatively small number of differently dimensioned bases will normally suffice to support pump housings varying from a minimum size to a maximum size whereby each base can support a given series of differently dimensioned housing. The number of differently dimensioned bases depends only on the desired number of output ranges. Such mode of constructing centrifugal pumps exhibits the advantage of necessitating a relatively small number of parts. How.- ever, it also exhibits a serious drawback, namely, that the conduit must be disconnected at least at the inlet side whenever it becomes necessary to remove or replace the impeller or runner of the centrifugal pump. This is undesirable, particularly in certain branches of the chemical and petro-chemical industry.

It was already proposed to assemble the housing of a centrifugal pump in such a way that the runner can be removed at the pressure or outlet side without necessitating a detachment of the fluid-supplying and fluidevacuting conduits from the housing. This solves certain problems and reduces the time which is necessary for removal or insertion of the runner. However, such proposal also exhibits serious drawbacks, particularly as concerns the complexity of the housing. Thus, whereas the construction of the housing at the suction side can be simplified because the sleeve for the shaft bearing can be made integral with the volute casing (so that this section of the housing requires a minimum of machining since it can be constructed as a one-piece casting), the complexity of the housing at the outlet side is greatly increased. The proposals to solve such problems at the outlet side of a housing wherein the volute casing is made of one piece with the sleeve for the shaft bearing include the provision of so-called lantern rings whose utilization results in a reduction in the number of necessary bearing carriers, or the utilization of a large number of bearing carriers but no lantern rings. It was found that such proposals fail to appreciably reduce the complexity and the manufacturing cost of the pump housing. Their main drawback is the need for a substantial number of discrete component parts.

with attendant problems as concerns the manufacturing cost, storage and the cost for assembly of the pump housing. For example, the number of sleeves for stuffing boxes depends on the required number of different diameters of runners which are needed for the entire series of pumps, on the number of necessary bearing carrier sizes, as well as on the need for different types of devices to compensate for axial hydraulic thrusts. The number of bearing carriers in a centrifugal pump of the just discussed type will depend not only on the desired number of output ranges but also on the number of utilized runner diameters. Moreover, the auxiliary equipment for the cooling or heating of stuffing boxes in such centrifugal pumps is quite complex and expensive; such equipment normally employs cooling covers or the like.

SUMMARY OF THE INVENTION An object of the invention is to provide a novel and improved housing for a centrifugal pump which is sim pler, more versatile and less expensive than presently known centrifugal pump housings.

Another object of the invention is to provide a housing whose components can be used for the assembly of centrifugal pumps with widely different outputs.

A further object of the invention is to provide a centrifugal pump housing which is constructed and assembled in such a way that it allows an operator to gain access to the runner without necessitating a substantial dismantling of the housing.

An additional object of the invention is to provide a novel and improved wearing ring for use in the housing of a centrifugal pump.

Still another object of the invention is to provide a centrifugal pump housing whose component parts occupy in storage less room than the component parts of presently known housings.

A further object of the invention is to provide a centrifugal pump housing which comprises fewer and simpler components than presently known housings.

The centrifugal pump housing of the present invention comprises an annular inlet section having a substantially radially extending flange member which is preferably integral with a shaft sleeve and a cylindrical portion for reception of one or more stuffing boxes, a volute casing, and a wearing ring member which is interposed between the flange member and the volute casing. In accordance with a feature of the invention, one of the members has several concentric first'annular ribs ofdifferent diameters and the other member has a second annular rib which is in sealing engagement with one of the first ribs. Thus, if the one member is the wearing ring member, such wearing ring member can be assembled with two or more differently dimensioned annular sections as long as each of the several sections comprises a flange member having a second. rib which can be placed into proper sealing engagement with one of several first ribs on the wearing ring member. If the one member is the flange member, any given section can be assembled with one of several differently dimensioned wearing ring members as long as each such wearing ring member comprises a rib which can be placed into proper sealing engagement with one rib of the flange member.

The novel features which are considered as characteristic of the invention are set forth in particular in the appended claims. The improved centrifugal pump housing itself, however, both as to its construction and its mode of operation, together with additional features and advantages thereof, will be best understood upon perusal of the following detailed description of certain specific embodiments with reference to the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a fragmentary axial sectional view of a centrifugal pump whose housing is constructed and assembled in accordance with a first embodiment of the invention;

FIG. 2 is a similar fragmentary axial sectional view of a centrifugal pump having a housing which is constructed and assembled in accordance with a second embodiment of the invention; and

FIG. 3 is a fragmentary axial sectional view of a centrifugal pump whose housing is constructed and assembled in accordance with a third embodiment of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring first to FIG. 1, there is shown a portion of a centrifugal pump whose housing comprises an annular inlet section I having a shaft sleeve 2, a cylindrical section 1 which accommodates the stuffing box SB and a radial flange member 3. The sleeve 2 surrounds the antifriction bearings (not shown) for the shaft 17 which drives an impeller or runner 9.

The flange member 3 is bolted to a wearing or sealing ring member 5 which is interposed between the flange member 3 and a volute casing 6. The flange member 3 has a concentric annular rib 4 the outer diameter of which matches the internal diameter of one of several concentric annular ribs (4', 4", 4") of the wearing ring member 5. The latter has a radially outwardly extending collar 7 which is bolted or screwed directly to the volute casing 6. An annular external surface 8 of the collar 7 is in sealing abutment with a complementary annular internal surface of the volute casing 6. The dimensions of the collar 7 and surface 8 depend on the diameter of the runner 9. In the embodiment of FIG. 1, the external surface of the rib 4 on the flange member 3 is sealingly engaged by a complementary internal surface of the outermost rib 4" on the wearing ring member 5. A single rib 4 ofa smaller flange member 3 forming part of a differently dimensioned annular section I (not shown) will be placed into sealing engagement with the internal surface of the rib 4 or 4" on the wearing ring member 5. Thus, the illustrated wearing ring member 5 can be assembled with at least two differently dimensioned annular inlet sections I. In the region of the radially innermost portion of the wearing ring member 5, there is provided a sealing element 10 which prevents leakage of fluid between the chamber for the runner 9 and a heating or cooling compartment 11 between the members 3 and 5. The diameters of the foremost parts of cylindrical portions 1 on housing section I of different sizes are preferably the same so that the illustrated wearing ring member 5 can properly seal the chamber for the runner 9 from the compartment 11 which is defined with a larger or smaller section I. If the centrifugal pump is designed for transport of a hot liquid (c.g., water), the compartment 11 will be used for the circulation of a suitable coolant which prevents excessive heating of the cylindrical portion 1 and stuffing box SB. If the quantities of heat which must be withdrawn in the region of the cylindrical portion 1 are relatively small, the compartment 11 can be subdivided into two or more smaller portions, e.g. by the provision of an axially extending partition 12 on the wearing ring member 5. In the embodiment of FIG. 1, the partition 12 carries the smallest-diameter rib 4 and subdivides the compartment 11 into an inner or cooling portion 11 and an outer portion 11b. The cooling action of fluid which circulates through the inner compartment portion 11a is very effective in the region of the cylindrical portion 1 of the housing section I. When the volute casing 6 contains a hot liquid, a port 15 in the wearing ring member 5 is sealed together with a port 16 in the cylindrical portion 1, and the ports 13, 14 in the flange member 3 are opened for circulation of a coolant which is drawn from a suitable source, not shown. If the compartment portion 11a is to be filed with a leakagepreventing liquid, the ports 13, 14 are sealed and the port 15 is opened together with the port 16 so that the liquid which is being compressed in the volute casing 6 can be admitted into the compartment portion 11a. The wearing ring member 5 can be provided with an annulus of sealable ports 15, the flange member 3 can be provided with several pairs of scalable ports 13, 14, and the cylindrical portion I can have several ports 16. If the pump of FIG. 1 is used for transport of corrosive fluids, the surfaces which come into contact with such fluids are coated with layers of material which can stand the corrosive influence.

In the embodiment of FIG. 1, the wearing ring member 5 can be used with at least two and preferably three differently dimensioned annular housing sections I, depending on the diameter of the rib 4 on the flange member 3 of the utilized section I. To this end, the wearing ring member 5 has at least two but preferably more concentric annular ribs 4, 4", 4" with annular surfaces each of which is complementary to the surface on the rib 4 of a differently dimensioned flange member 3. The number of ribs on the wearing ring member 5 will depend on the number of differently dimensioned housing sections I which can be utilized with a particular runner 9 and volute casing 6, i.e., on the number of differently dimensioned housing sections l which can be used with the parts 5,6, and 9 for achieving a particular range of output. The sealing element 10 can be omitted if the radially innermost portion of the wearing ring member 5 engages the cylindrical portion 1 of the annular section I with a requisite sealing action or if the clearance between the cylindrical portion 1 and the radially innermost portion of the wearing ring member 5 is within the permissible range. If desired, the sealing action between the innermost portion of the wearing ring member 5 and'the cylindrical portion 1 of the annular section I can be achieved by utilizing a detachable flange or ring, not shown. As mentioned before, the outer diameters of the foremost parts of cylindrical portions 1 on all sections I which are intended for assembly with the parts 5, 6, 9 of FIG. 1 are preferably such that the cylindrical portion of the selected section I is receivable in the radially innermost portion of the wearing ring member 5 (at the sealing element 10) with a predetermined clearance. The pump housing section (not shown) at the discharge end need not be dismantled if the operator wishes to gain access to the runner 9; the operator then simply removes the section I and the wearing ring 5 whereby the runner 9 is freely accessible at the right-hand side of the volute casing 6. The minimum diameter of the external surface 8 exceeds the maximum diameter of the runner 9.

FIG. 2 illustrates a portion of a second centrifugal pump wherein the housing constitutes a simplified version of the housing shown in FIG. 1. The dimensions of the annular housing section II, wearing ring member 105 and volute casing 106 are selected in such a way that the collar 107 of the wearing ring member 105 is insertable between the radially outermost portion of the section II and the volute casing 106. The external cylindrical surface 108 of the wearing ring member 105 has the same diameter as the adjacent internal cylindrical surface of the volute casing 106. Furthermore, the diameter of the surface 108 equals the diameter of the external surface of the single concentric rib 104 on the flange member 103. The rib 104 engages the outer one of the two concentric annular ribs 104', 104" on the wearing ring member 105. Such dimensioning enhances the appearance of the pump housing. It will be noted that the external surfaces of the collar 107, flange 103 and the adjoining portion of the casing 106' have identical diameters. All other parts of the pump shown in FIG. 2 are analogous to the corresponding parts of the pump which is illustrated in FIG. 1 and are denoted by similar reference characters plus 100. The

wearing ring member 105 can be assembled with at one of which is engaged by the rib 204' on the wearing ring member 205. This wearing ring member 205 is one of several wearing ring members which can be used with the housing section III for the assembly of a complete housing. The wearing ring member 205 is further sealingly connected with a volute 206 which surrounds an impeller or runner 209. The parts 205 and III of the housing shown in FIG. 3 define a single compartment 211 and the ports 213, 214, 215, 216 shown in FIG. 3 perform the same functions as the similarly referenced ports of FIG. 1. The housing of FIG. 3 bears acertain resemblance to the housing of FIG. 2 insofar as the diameters of the internal surface of the rib 204' and of the external annular surface 208 on the wearing ring member 205 are identical. The parts denoted by the characters 201,202,207,2l0 are identical with the similarly referenced parts of FIG. 1 or 2.

In order to enhance the appearance of the housing of FIG. 3when the section III is assembled with a wearing ring member whose rib 204' is in sealing engagement with one of the smaller-diameter ribs 204, 2040 of the flange member 203, the outermost portion of the flange member 203 can be removed by machining. This not only enhances the appearance of the housing but also allows for a more efficient insulation of the housing from the outside (all the way to the collar 207), for example, when the centrifugal pump is to transport a hot liquid. The diameter of the surface 208 equals the diameter of the external surface on the rib 204b.

The main difference between the construction of FIGS. 1 and 3 is that the flange 3 of the annular section I has a single rib 4 and the wearing ring member 5 has several ribs 4,4",4" one of which can be sealingly engaged by the rib 4 on a differently dimensioned flange member 3, whereas the wearing ring member 205 has a single rib 204' but the flange member 203 of the section III has several concentric ribs 204, 204a, 204b so that the section III can be assembled with a number of differently dimensioned wearing ring members 205 and volute casings 206.

The improved pump housing exhibits the advantage that it can remain closed atthe discharge or outlet side and that the parts at the inlet side are constructed and assembled in such a way that a smaller number of such parts is necessary to assemble an entire range of contrifugal pumps which can employ at least one ofa series of identically dimensioned parts, such as the parts 5, 6, 9 of FIG. 1 or the annular section III of FIG. 3. The advantages of a pump housing which can remain closed at the outlet side when the operator wishes to gain access to the runner were outlined hereinbefore.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can, by applying current knowledge, readily adapt it for various applications without omitting features which fairly constitute essential characteristics of the generic and specific aspects of our contribution to the art and, therefore, such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the claims.

What is claimed as new and desired to be protected by Letters Patent is set forth in the appended claims:

1. In a centrifugal pump, a housing comprising an annular section constituting a one-piece casting having a substantially radially extending flange member; a volute casing; and a wearing ring member interposed between said casing and said flange member, one of said members having a plurality of first annular sealing ribs and the other of said members having a second annular sealing rib in sealing engagement with one of said first ribs.

2. A housing as defined in claim 1, wherein the diameters of said first sealing ribs are different.

3. In a centrifugal pump, a housing comprising an annular section having a substantially radially extending flange member, a shaft sleeve and a cylindrical portion coaxial with said shaft sleeve, said shaft sleeve being integral with said flange member and said cylindrical portion; a volute casing; and a wearing ring member interposed between said casing and said flange member, one of said members having a plurality of first annular sealing ribs and the other of said members having a second annular sealing rib in sealing engagement with one of said first ribs.

4. A housing as defined in claim 3, wherein said wearing ring member has a concentric external surface and said volute casing has a concentric internal annular surface sealingly surrounding said external surface of said ring member.

5. A housing as defined in claim 4, wherein said members define an annular compartment surrounding said cylindrical portion.

6. A housing as defined in claim 4, wherein said second rib and said one first rib have abutting annular surfaces of a predetermined diameter which at least approximates the diameters of said first mentioned annular surfaces.

7. A housing as defined in claim 3, wherein said wearing ring member further comprises a radially innermost portion having a first predetermined internal diameter and said cylindrical portion includes an external surface having a second predetermined diameter and being surrounded by said internal surface, said other member forming part of a plurality of differently dimensioned other members each having a second annular rib which is movable into sealing engagement with one of said first ribs and the diameters of surfaces on each of said series of other members being identical.

8. In a centrifugal pump, a housing comprising an annular section having a substantially radially extending flange member; a volute casing; a wearing ring member interposed between said casing and said flange member, one of said members having a plurality of first annular sealing ribs and the other of said members having a second annular sealing rib in sealing engagement with one of said first ribs; and a plurality of additional other members each having a second sealing rib, each of said additional other members being assemblable with said one member as a substitute for said first mentioned other member and the second sealing rib of each additional other member being movable into sealing engagement with one of said first ribs.

9,. In a centrifugal pump, a housing comprising an annular section having a substantially radially extending flange member; a volute casing; and a wearing ring member interposed between said casing and said flange member, one of said members having a plurality of first annular sealing ribs and the other of said members having a second annular sealing rib in sealing engagement with one of said first ribs, said section defining with said wearing ring member an annular compartment and said wearing ring member having at least one sealable first port adapted to establish communication between said compartment and the interior of said volute casing, said flange member having at least one sealable second port adapted to communicate with said compartment and said section further having a cylindrical portion provided with at least one sealable third port adapted to communicate with said compartment. 

1. In a centrifugal pump, a housing comprising an annular sectIon constituting a one-piece casting having a substantially radially extending flange member; a volute casing; and a wearing ring member interposed between said casing and said flange member, one of said members having a plurality of first annular sealing ribs and the other of said members having a second annular sealing rib in sealing engagement with one of said first ribs.
 2. A housing as defined in claim 1, wherein the diameters of said first sealing ribs are different.
 3. In a centrifugal pump, a housing comprising an annular section having a substantially radially extending flange member, a shaft sleeve and a cylindrical portion coaxial with said shaft sleeve, said shaft sleeve being integral with said flange member and said cylindrical portion; a volute casing; and a wearing ring member interposed between said casing and said flange member, one of said members having a plurality of first annular sealing ribs and the other of said members having a second annular sealing rib in sealing engagement with one of said first ribs.
 4. A housing as defined in claim 3, wherein said wearing ring member has a concentric external surface and said volute casing has a concentric internal annular surface sealingly surrounding said external surface of said ring member.
 5. A housing as defined in claim 4, wherein said members define an annular compartment surrounding said cylindrical portion.
 6. A housing as defined in claim 4, wherein said second rib and said one first rib have abutting annular surfaces of a predetermined diameter which at least approximates the diameters of said first mentioned annular surfaces.
 7. A housing as defined in claim 3, wherein said wearing ring member further comprises a radially innermost portion having a first predetermined internal diameter and said cylindrical portion includes an external surface having a second predetermined diameter and being surrounded by said internal surface, said other member forming part of a plurality of differently dimensioned other members each having a second annular rib which is movable into sealing engagement with one of said first ribs and the diameters of surfaces on each of said series of other members being identical.
 8. In a centrifugal pump, a housing comprising an annular section having a substantially radially extending flange member; a volute casing; a wearing ring member interposed between said casing and said flange member, one of said members having a plurality of first annular sealing ribs and the other of said members having a second annular sealing rib in sealing engagement with one of said first ribs; and a plurality of additional other members each having a second sealing rib, each of said additional other members being assemblable with said one member as a substitute for said first mentioned other member and the second sealing rib of each additional other member being movable into sealing engagement with one of said first ribs.
 9. In a centrifugal pump, a housing comprising an annular section having a substantially radially extending flange member; a volute casing; and a wearing ring member interposed between said casing and said flange member, one of said members having a plurality of first annular sealing ribs and the other of said members having a second annular sealing rib in sealing engagement with one of said first ribs, said section defining with said wearing ring member an annular compartment and said wearing ring member having at least one sealable first port adapted to establish communication between said compartment and the interior of said volute casing, said flange member having at least one sealable second port adapted to communicate with said compartment and said section further having a cylindrical portion provided with at least one sealable third port adapted to communicate with said compartment. 